<< " -- BB#" << NMBB->getNumber()
<< " -- BB#" << Succ->getNumber() << '\n');
+ // On some targets like Mips, branches may kill virtual registers. Make sure
+ // that LiveVariables is properly updated after updateTerminator replaces the
+ // terminators.
+ LiveVariables *LV = P->getAnalysisIfAvailable<LiveVariables>();
+
+ // Collect a list of virtual registers killed by the terminators.
+ SmallVector<unsigned, 4> KilledRegs;
+ if (LV)
+ for (iterator I = getFirstTerminator(), E = end(); I != E; ++I) {
+ MachineInstr *MI = I;
+ for (MachineInstr::mop_iterator OI = MI->operands_begin(),
+ OE = MI->operands_end(); OI != OE; ++OI) {
+ if (!OI->isReg() || !OI->isUse() || !OI->isKill() || OI->isUndef())
+ continue;
+ unsigned Reg = OI->getReg();
+ if (TargetRegisterInfo::isVirtualRegister(Reg) &&
+ LV->getVarInfo(Reg).removeKill(MI)) {
+ KilledRegs.push_back(Reg);
+ DEBUG(dbgs() << "Removing terminator kill: " << *MI);
+ OI->setIsKill(false);
+ }
+ }
+ }
+
ReplaceUsesOfBlockWith(Succ, NMBB);
updateTerminator();
if (i->getOperand(ni+1).getMBB() == this)
i->getOperand(ni+1).setMBB(NMBB);
- if (LiveVariables *LV =
- P->getAnalysisIfAvailable<LiveVariables>())
+ // Update LiveVariables.
+ if (LV) {
+ // Restore kills of virtual registers that were killed by the terminators.
+ while (!KilledRegs.empty()) {
+ unsigned Reg = KilledRegs.pop_back_val();
+ for (iterator I = end(), E = begin(); I != E;) {
+ if (!(--I)->addRegisterKilled(Reg, NULL, /* addIfNotFound= */ false))
+ continue;
+ LV->getVarInfo(Reg).Kills.push_back(I);
+ DEBUG(dbgs() << "Restored terminator kill: " << *I);
+ break;
+ }
+ }
+ // Update relevant live-through information.
LV->addNewBlock(NMBB, this, Succ);
+ }
if (MachineDominatorTree *MDT =
P->getAnalysisIfAvailable<MachineDominatorTree>()) {
--- /dev/null
+; RUN: llc < %s -verify-coalescing
+; PR10046
+;
+; PHI elimination splits the critical edge from %while.end415 to %if.end427.
+; This requires updating the BNE-J terminators to a BEQ. The BNE instruction
+; kills a virtual register, and LiveVariables must be updated with the new kill
+; instruction.
+
+target datalayout = "E-p:32:32:32-i1:8:8-i8:8:32-i16:16:32-i32:32:32-i64:32:64-f32:32:32-f64:64:64-v64:64:64-n32"
+target triple = "mips-ellcc-linux"
+
+define i32 @mergesort(i8* %base, i32 %nmemb, i32 %size, i32 (i8*, i8*)* nocapture %cmp) nounwind {
+entry:
+ br i1 undef, label %return, label %if.end13
+
+if.end13: ; preds = %entry
+ br label %while.body
+
+while.body: ; preds = %while.body, %if.end13
+ %list1.0482 = phi i8* [ %base, %if.end13 ], [ null, %while.body ]
+ br i1 undef, label %while.end415, label %while.body
+
+while.end415: ; preds = %while.body
+ br i1 undef, label %if.then419, label %if.end427
+
+if.then419: ; preds = %while.end415
+ %call425 = tail call i8* @memmove(i8* %list1.0482, i8* undef, i32 undef) nounwind
+ br label %if.end427
+
+if.end427: ; preds = %if.then419, %while.end415
+ %list2.1 = phi i8* [ undef, %if.then419 ], [ %list1.0482, %while.end415 ]
+ tail call void @free(i8* %list2.1)
+ unreachable
+
+return: ; preds = %entry
+ ret i32 -1
+}
+
+
+declare i8* @memmove(i8*, i8*, i32)
+
+declare void @free(i8*)
+